1. Field of the Invention
The present invention relates, in general, to an oil level sensing device for sensing the amount of oil in an oil pan of an internal combustion engine and, more particularly, to an oil level sensing device capable of simply informing a driver in a driver's seat of an oil shortage by selectively generating an alarm signal when the amount of oil in the oil pan is reduced to less than a preferred amount.
2. Description of the Prior Art
As well known to those skilled in the art, internal combustion engines for automobiles are individually provided with an oil pan, which is used for storing engine oil therein. In order to check the amount of oil in such an oil pan, the oil pan is provided with an oil level checking device. FIG. 3 shows the construction of a typical oil level checking device for oil pans. As shown in the drawing, the typical device for checking the amount of oil in an oil pan 2 is comprised of an oil guide pipe 3, which is vertically positioned in the oil pan 2. An oil checking rod 4, which is used for checking the amount of oil in the oil pan 2, is detachably inserted in the guide pipe 3, thus being selectively pulled out from the pipe 3.
Two points, that is, top and bottom points 4a and 4b, are marked on the oil checking rod 4, with an interval being formed between the two points 4a and 4b. In order to check the amount of oil in the oil pan 2, the oil checking rod 4 is pulled out from the guide pipe 3 prior to checking the position or the height of oil line on the oil checking rod 4.
That is, a driver, who wants to check the amount of oil in the oil pan 2, pulls the oil checking rod 4 from the guide pipe 4 of the oil pan 2 and checks the amount of oil by determining the position of oil adhering to the rod 4 between the two points 4a and 4b. In such a case, when the height line of oil adhering onto the rod 4 is positioned between the two points 4a and 4b, the amount of oil in the oil pan 2 is acceptable, thus being free from any necessity of addition or change of engine oil. Meanwhile, when the height line of oil on the rod 4 fails to reach at least the bottom point 4b, engine oil has to be added or changed. On the other hand, the engine oil in the oil pan 2 may be changed with new oil after checking the turbidity of the oil. In order to check the turbidity of the oil, it is necessary to determine the color of the oil adhering onto the rod 4 after pulling the rod 4 from the guide pipe 3.
However, such an oil level checking device is problematic in that a driver, who wants to determine whether the engine oil has to be added or changed, has to manually pull the oil checking rod 4 from the guide pipe 3 of the oil pan 2.